Ajax Frameworks
The best technology to build dynamic web pages is Ajax.
JavaScript code embedded into the HTML page is used to send requests to the
server. At the server side, some processing is required to handle them, find
the info or store the data. To do that, we need for a specialized framework.
The framework has always a JavaScript part, and sometimes a server side part
in another scripting language. A lot of them exist in various programming
languages, in all environments around, but we retain here only the most widely
used.
Why a framework?
Actually, this framework is the Ajax engine described by J. J. Garrett and
intended to suppress waiting for the user when accessing the server.
The framework provides classical, cross-browser functions to use the XMLHttpRequest
object. But a framework may goes beyond that, and allow to build "rich
web applications", applications with a graphical user interface and other
features of desktop software that run through a browser, while exchanging
data with a remote server.
Features of an Ajax framework
Any Ajax framework is able to communicate with the server, and thus, to read
data or to send it data or commands. In the last case a server-side script
is required.
The frameworks often add components that make use of the asynchronous communication
with the server.
The classical examples are buttons, tabbed panels, grids, listboxs and other
such widgets.
A more innovative example, the "boxes", are more and more often
implemented, and Lightbox and Slimbox are two of them. There are image galleries
that place them side by side on the screen and that are making use of Ajax
to display them instantanously .
Framework may be server-driven also, and in this case, component are created
on the server with a scripting language such as PHP, and sent to the browser.
Ajax is used to transmit user actions to the server part, and to handle the
results.
The ability to work offline as it is offered by HTML 5 is a complement to the Ajax framework as well.
What Ajax framework to choose?
You want to use an Ajax framework to make dynamic pages without having to rewrite the whole stuff youself and test it on all browsers...
But they are so numerous that you wonder which one to use. You want not make a bad choise and be forced later to redo all the pages with a different framework!
You are less likely to regret the choice of a framework if you adopt one of the most used because they are continually supplemented by new extensions and have a good support by users.
Among these, there are jQuery, well documented, Mootools that is modular, Ext JS offering many widgets for RIA.
The interaction with a server side language also should guide the choice.